A glass-based circuit board and a method of manufacturing the same

Abstract

The application provides a glass-based circuit board and a preparation method thereof, and the preparation method comprises the following steps: S1, preparing a conductive paste, wherein the conductive paste comprises a conductive metal and an organic binder; S2, applying the conductive paste on a glass substrate by printing; and S3, sintering the glass substrate coated with the conductive paste by laser to obtain the glass-based circuit board. The preparation method of the glass-based circuit board provided by the application forms a transient high temperature on the surface of the glass in a very short time by laser sintering based on the characteristics of the glass substrate and the conductive paste, which does not damage the strength of the glass substrate itself, and can completely sinter and solidify the ink, so that the conductive circuit and the glass substrate become an integrated structure, the adhesion between the conductive circuit and the glass substrate is improved, meanwhile, only metal conductive particles are left in the conductive circuit layer, the conductivity of the conductive circuit layer can be greatly improved, and the square resistance is reduced.

Description

Technical Field

[0001] This invention relates to the field of touchscreen manufacturing technology, and more specifically, to a glass-based circuit board and its manufacturing method. Background Technology

[0002] Glass-based circuit boards have good temperature and aging resistance and are not easily deformed. Existing glass-based circuit boards are usually fabricated by printing conductive paste onto the glass substrate and then baking it at a temperature of about 200°C for 15 minutes to obtain the circuit.

[0003] In order to ensure the adhesion between the circuit and the glass substrate, a large amount of binder needs to be added to the conductive paste when preparing glass-based circuit boards by baking. This results in a low content of conductive components in the prepared circuit, which in turn leads to a large sheet resistance and low conductivity.

[0004] High conductivity inks often require high-temperature sintering to obtain conductive circuit layers with good mechanical strength. The sintering temperature is generally above 500-600℃ and the sintering time is above 10 minutes. Many glass-based conductive circuit boards have high requirements for the strength of the glass, and often require tempering of the glass substrate. The physical tempering temperature is above 550℃ and the chemical tempering temperature is above 400℃. When the sintering temperature of the conductive circuit layer is close to or higher than the tempering temperature of the glass, the glass substrate is prone to de-tempering, resulting in a decrease in glass strength. This makes it difficult for high conductivity inks to be widely used in glass-based circuit boards. Summary of the Invention

[0005] The problem solved by this invention is that highly conductive inks are difficult to use widely on glass-based circuit boards.

[0006] To address the above problems, this invention provides a method for preparing a glass-based circuit board, comprising the following steps:

[0007] S1. Prepare a conductive paste, wherein the conductive paste comprises a conductive metal and an organic binder;

[0008] S2. The conductive paste is applied to the glass substrate by printing.

[0009] S3. A glass substrate coated with conductive paste is sintered using a laser to obtain a glass-based circuit board.

[0010] Specifically, the process conditions for sintering a glass substrate coated with conductive paste using a laser are a sintering temperature of 600℃ and a sintering time of 2-3 seconds.

[0011] Specifically, the thickness of the glass substrate ranges from 0.55mm to 4.0mm.

[0012] Specifically, the conductive metal in the conductive paste has a mass percentage content of 80%-90%.

[0013] Specifically, the conductive metal is selected from at least one of silver powder, copper powder, and silver-coated copper powder.

[0014] Another object of the present invention is to provide a glass-based circuit board, which is prepared by the glass-based circuit board preparation method described above.

[0015] The method for preparing a glass substrate circuit board provided by this invention, based on the characteristics of the glass substrate and the conductive paste, uses laser sintering to form an instantaneous high temperature on the glass surface in a very short time. This method does not damage the strength of the glass substrate itself, but also completely sintersects and solidifies the ink, making the conductive lines and the glass substrate an integrated structure. This improves the adhesion between the conductive lines and the glass substrate. At the same time, the high temperature of 600°C decomposes the organic crosslinking agent in the conductive paste, leaving only metal conductive particles in the conductive line layer. This can significantly improve the conductivity of the conductive line layer, reduce the sheet resistance, thereby improving the performance of the glass-based circuit board and expanding its application range. Detailed Implementation

[0016] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "circumferential," and "radial," etc., indicating orientation or positional relationships, are only for the purpose of simplifying the description and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0018] Furthermore, the terms "first" and "second" are used only for simplification and should not be construed as indicating or implying relative importance, or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0019] In this invention, unless otherwise explicitly specified and limited, "above" or "below" a first feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a first feature above a second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a first feature below a second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0020] The present invention will now be described in detail.

[0021] To address the challenge of using highly conductive inks on glass-based circuit boards, this invention provides a method for preparing a glass-based circuit board, comprising the following steps:

[0022] S1. Prepare a conductive paste, wherein the conductive paste comprises a conductive metal and an organic binder;

[0023] S2. The conductive paste is applied to the glass substrate by printing.

[0024] S3. A glass substrate coated with conductive paste is sintered using a laser to obtain a glass-based circuit board.

[0025] Both the conductive paste and the glass substrate can be selected from existing technologies according to actual needs; the conductive paste can be directly selected from existing high-conductivity inks; the printing method in step S2 can be screen printing; the printing pattern can be set independently according to the circuit requirements; since laser sintering uses a laser as a heat source, the temperature can reach 600℃ in a short time, thus completing the sintering of the conductive paste without having to sinter the glass substrate at high temperatures for a long time; during the short-time high-temperature laser sintering process, on the one hand, the conductive paste coated on the surface of the glass substrate forms a conductive circuit without damaging the glass substrate, and the conductive circuit and the glass substrate form an integral structure, which helps to improve the adhesion between the conductive circuit and the glass substrate; on the other hand, during the sintering process, the organic binder, i.e., the organic crosslinking agent in the conductive paste, decomposes, so that only metal conductive particles remain in the prepared conductive circuit, which can significantly improve the conductivity of the conductive circuit layer and reduce the sheet resistance.

[0026] The method for preparing a glass substrate circuit board provided by this invention, based on the characteristics of the glass substrate and the conductive paste, uses laser sintering to form an instantaneous high temperature on the glass surface in a very short time. This method does not damage the strength of the glass substrate itself, but completely sintersulates and solidifies the ink, making the conductive lines and the glass substrate an integrated structure. This improves the adhesion between the conductive lines and the glass substrate and solves the problem that high-conductivity inks are difficult to use on glass-based circuit boards. At the same time, the high temperature of 600°C decomposes the organic crosslinking agent in the conductive paste, leaving only metal conductive particles in the conductive line layer. This can significantly improve the conductivity of the conductive line layer, reduce sheet resistance, thereby improving the performance of the glass-based circuit board and expanding its application range.

[0027] To balance the mechanical and electrical properties of glass-based circuit boards, this application preferably uses laser sintering of glass substrates coated with conductive paste under the following process conditions: sintering temperature 600℃ and sintering time 2-3 seconds.

[0028] The preferred thickness of the glass substrate in this application is 0.55mm-4.0mm.

[0029] When manufacturing circuit boards using traditional sintering methods, if the sintering temperature is low, it is difficult to sinter the organic binder in the conductive paste, thus making it difficult to improve the conductivity of the glass-based circuit board. To achieve the sintering of the organic binder, it is necessary to sinter the glass substrate coated with conductive paste at a high temperature of around 600°C for a long time. During long-term high-temperature sintering, the glass substrate is kept above the tempering temperature for a long time, which easily causes the glass substrate to de-temper, resulting in a decrease in the strength of the glass substrate.

[0030] This application employs laser sintering, which enables sintering to be completed in a very short time. This avoids the glass substrate being exposed to tempering temperatures for extended periods, allowing for the fabrication of integrated conductive lines with good adhesion, high metal content, and high conductivity on the glass substrate without reducing its strength. This, in turn, helps improve the performance of glass-based circuit boards, enables thinner designs of glass-based circuit boards, and expands the application range of glass-based circuit boards.

[0031] To ensure the conductivity of the glass-based circuit board and the adhesion between the conductive lines and the glass substrate, this application preferably uses a conductive metal content of 80%-90% by mass in the conductive paste.

[0032] When glass-based circuit boards are prepared using traditional baking methods, if the content of organic binder in the conductive paste is too low, it is difficult to ensure the adhesion between the conductive lines and the glass substrate. Conversely, if the content of organic binder in the conductive paste is too high, it will result in the content of conductive metal in the conductive lines being too low, thus causing the sheet resistance of the glass-based circuit board to be too high and the conductivity to be too low.

[0033] This application utilizes laser sintering to sinter the organic binder in a short time. Simultaneously, during sintering, the conductive metal and glass substrate become an integral structure, forming a conductive circuit. Therefore, even with a high content of organic binder in the conductive paste, the conductive metal content in the conductive circuit after sintering is guaranteed, thus ensuring conductivity while reducing the amount of conductive metal used and lowering costs. Conversely, even with a low content of organic binder in the conductive paste, the conductive metal becomes an integral structure with the glass substrate after laser sintering, ensuring adhesion between the conductive circuit and the glass substrate. Therefore, the mass ratio of conductive metal to organic binder in the conductive paste of this application can be selected within a wide range.

[0034] To ensure the conductivity of the glass-based circuit board, this application preferably selects the conductive metal from at least one of silver powder, copper powder, and silver-coated copper powder.

[0035] The silver-coated copper powder can be selected from existing technologies.

[0036] Another object of the present invention is to provide a glass-based circuit board, which is prepared by the glass-based circuit board preparation method described above.

[0037] The glass-based circuit board provided by this invention, based on the characteristics of the glass substrate and conductive paste, forms an instantaneous high temperature on the glass surface in a very short time through laser sintering. This process does not damage the tempering effect of the glass substrate, but completely sintersects and solidifies the ink, making the conductive lines and the glass substrate an integrated structure. This improves the adhesion between the conductive lines and the glass substrate. At the same time, the high temperature of 600°C decomposes the organic crosslinking agent in the conductive paste, leaving only metal conductive particles in the conductive line layer. This significantly improves the conductivity of the conductive line layer, reduces sheet resistance, and thus improves the performance of the glass-based circuit board, expanding its application range.

[0038] While the disclosure is as stated above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this invention.

Claims

1. A method for fabricating a glass-based circuit board, characterized in that, Includes the following steps: S1. Prepare a conductive paste, wherein the conductive paste comprises a conductive metal and an organic binder; the mass percentage of the conductive metal in the conductive paste is 80%-90%; the conductive metal is selected from at least one of silver powder, copper powder, and silver-coated copper powder. S2. The conductive paste is applied to the glass substrate by printing. S3. A glass substrate coated with conductive paste is sintered using a laser to obtain a glass-based circuit board. The process conditions for sintering a glass substrate coated with conductive paste by laser are a sintering temperature of 600℃ and a sintering time of 2-3 seconds.

2. The method for preparing a glass-based circuit board according to claim 1, characterized in that, The thickness of the glass substrate ranges from 0.55mm to 4.0mm.

3. A glass-based circuit board, characterized in that, The glass-based circuit board is prepared by the method described in any one of claims 1-2.